No luck with acetone.
Also i had actual pieces of PBW stuck on the glass. Little chunks. There was also a couple small white spots, but i was more worried about the little chunks.
SO far ISO, iso/salt and shaking, vinegar, acetone, dish soap, near boiling water... All with shaking...All failed. I have been trying and soaking since yesterday evening.
HOWEVER... I managed to get it off, i took rock salt... the kind you throw out on the sidewalks and roads for snow, and put quite a bit in it, even the hard gravel like pieces. if it would fit, it went in.
Then i added just a bit of cold water, i didnt want to dissolve the salt, and wanted more of a paste than a liquid.... and then i shook like hell.... At this point i didnt care if i scratched the glass on the inside, i just wanted the chunks of PBW out. I dont notice any scratches either... But a few pieces of the rocks did get caught up in the perc.... A few hot water rinses and they were all out as well though.
I believe im retiring PBW. Only 2-3 teaspoons used but i cant say im a fan. It never did remove the brown stain and caused more headache than the stain itself. Obviously this is likely my fault for how i used it or something... but ISO has never caused me ANY headache at all. It didnt get the stain out... but nothing has, so i cant fault ISO.